Information about the Luxfer recall / exchange 6351 alloy

[Warren_L]

Actually I happen to be reading this thread for the first time today as well, incidentally because I had a dive shop recently refuse a tank I brought them for a fill. They claim it was a Walter Kidde tank. My question is, how can the average diver tell if their tank is from a suspect manufacturer such as Walter Kidde? Is there a listing out there of all the tank manufacturer's stamps?

I am not familiar with the Walter Kidde tanks, but I thought the manufacturer was stamped into the top of the tank near the neck, is it not?

 

[pasley]

I am not familiar with the Walter Kidde tanks, but I thought the manufacturer was stamped into the top of the tank near the neck, is it not?

Easy, If is says CATALINA, it is not of the suspect alloy. If not it is. Of course it is more complicated than that. But Catalina never used the suspect alloy, almost everyone else did including Walter Kiddie.

At the top of the tank the alloy is stamped as E**** where the * is DOT exemption number.
The below is not an all inclusive list. Check DOT website yourself. You can search on the alloy numbers from your tank.

All DOT-3AL tanks manufactured under one of the following exemptions or special permits: 6498, 7042, 8107, 8364, 8422
All composite cylinders manufactured under one of the following exemptions: 7235, 8023, 8115
All Walter Kidde DOT-3AL scuba tanks.
All Cliff Impact DOT-3AL scuba tanks made before July 1990.
All Luxfer 80.8 cu. ft. scuba tanks (S80.8) made before May 1987.
All Luxfer 72 and 100 cu. ft. scuba tanks (S72, S100) made before August 1987.
All Luxfer 80 cu. ft. scuba tanks (S80) made before January 1988.
All Luxfer 50 and 92 cu. ft. scuba tanks (S50, S92) made before April 1988.
All Luxfer 30 and 63 cu. ft scuba tanks (S30, S63) made before May 1988.
All Luxfer 40 cu. ft. scuba tanks (S40) made before June 1988.
All other scuba tanks made in the US before February 1990 (except Catalina).
All scuba tanks not made in the US.
Unless proven otherwise, all scuba tanks in the above list should be assumed as being made using the 6351-T6 alloy.

 

[Laser]

I am not familiar with the Walter Kidde tanks, but I thought the manufacturer was stamped into the top of the tank near the neck, is it not?

WK = Walter Kiddie
Pst = Pressed Steel
M8303 = Faber
Heiser-M8304 = Heiser
"N" inside a diamond = Norris
"C" inside a diamond = Coyne
"TW" inside a circle = Taylor Wharton
Luxfer = Luxfer
ALCAN with a triangle over it = Alcan
M4002 or Catalina = Catalina
Cliff Impact Division = Parker
KAE = Kaiser
Scubapro and OMS are Fabers

 

[Delta_P]

Thank you for pointing out I'm a bit "late"...sorry, just found this board after some issues came up with some friends (I don't get out much....)....

You're not alone, it would seem.

T...BTW, I bought a Luxfer tank brand new in 2000, the first time it went through the VIP PLUS one year later, it FAILED! I had to ship it MY cost back to Luxfer, who okayed it and sent it back (MY COST) to me.....

Eddy current tests are not appropriate for 6061 alloy cylinders. This has been talked about for several years, but the dive shops haven't got the memo yet. Luxfer released the official word this spring, I guess after too many tales like yours.

http://www.luxfercylinders.com/news/releases/20040204a.shtml


I too thought that 6061 was a relatively new alloy, but according to our PSI VIP instructor the USN was using 6061 alloy cylinders in the 1950's,